The tk::imagewindow command creates a new window (given by the
pathName argument) and makes it into an imagewindow widget.
Additional options, described above, may be specified on the
command line or in the option database
to configure aspects of the imagewindow such as its background color
and relief. The tk::imagewindow command returns the
path name of the new window.
At the time this command is invoked, there must not
exist a window named pathName, but pathName's parent must exist.

An imagewindow is a widget which displays images. This includes the display
of animated GIF images.

The tk::imagewindow command creates a new Tcl command whose
name is the same as the path name of the imagewindow's window.
This command may be used to invoke various
operations on the widget. It has the following general form:

pathNameoption?arg arg ...?

PathName is the name of the command, which is the same as
the imagewindow widget's path name. Option and the args
determine the exact behavior of the command. The following
commands are possible for imagewindow widgets:

Query or modify the configuration options of the widget.
If no option is specified, returns a list describing all of
the available options for pathName (see Tk_ConfigureInfo for
information on the format of this list). If option is specified
with no value, then the command returns a list describing the
one named option (this list will be identical to the corresponding
sublist of the value returned if no option is specified). If
one or more option-value pairs are specified, then the command
modifies the given widget option(s) to have the given value(s); in
this case the command returns an empty string.
Option may have any of the values accepted by the imagewindow
command.

Specifies the contents of the image as a string. The string imageData
should contain base64-encoded data. The format of the string must be one
of those for which there is an image file format handler that will accept
string data.

If no argument is given the minimal delay time will be returned.
Otherwise this command manipulates the animation time. The minimum
delay is given with mindelay, that means the delay time
between two frames will not be less than mindelay.

Save all changes of the animation time to the file given with
filename. The file name is required because it is likely that
the file name of the image has changed in the meanwhile. The
save fails if the file given with filename does not have the
same file size as the original image file - this is a minimal
safety check because this command is not writing a new file, it
is overwriting the values of the given file.

If no argument is given the slow down factor will be returned.
Otherwise this command will be used to slow down the animation time
with the factor given by floatValue. But if the factor is
less than 1.0 the animation time will be faster.

Note that animation of animated GIFs will not be started automatically,
you have to use the command start.
If an image widget with active animation becomes unmapped the animation
stops, and restarts (at the first frame) if the widget becomes mapped.
If an image window becomes unvisible the animation will pause until
the widget is visible again.